1. Field of the Invention
The present invention generally relates to a mobile communication terminal having a smart card and being capable of receiving digital broadcasting, and in particular, to a digital broadcasting conditional access terminal and method for implementing a digital broadcasting Conditional Access System (CAS).
2. Description of the Related Art
A CAS indicates a system for authorizing an access to pay broadcasting services. A broadcasting station providing pay broadcasting services scrambles a broadcasting signal before transmission and a receiver descrambles the received broadcasting signal, thereby allowing only an authorized subscriber to enjoy the provided pay broadcasting services.
When a broadcasting station takes free broadcasting as a fundamental policy, the CAS cannot be used. However, when such a broadcasting station requires billing for some reasons (e.g., broadcasting subscription in shadow areas or subscription for contents requiring billing), an appropriate CAS should be implemented.
A mobile communication terminal equipped with a smart card has recently been developed, and user data and other data are stored in a flash memory of the smart card.
One of the representative uses of the smart card is to provide a roaming service of the mobile communication terminal with a mobile communication terminal user identity module embedded in the smart card. Examples of the mobile communication terminal user identity module include a Subscriber Identify-Module (SIM) card of a Universal Mobile Telecommunication System (UMTS), a Universal Subscriber Identity Module (USIM) of a Global System for Mobile Communications (GSM) system, and a User Identity Module (UIM) card, a Removal User Identity Module (RUIM) of a Code Division Multiple Access (CDMA) system, and a Surface Mount Device (SMD). The smart card having the mobile communication terminal user identity module embedded therein is basically used in a contact manner to share data with the mobile communication terminal.
For example, a GSM mobile communication terminal adopting European mobile communication standards uses the SIM card as the mobile communication terminal user identity module that serves as an interface between a mobile communication terminal and a network to deal with a situation, such as the replacement of the mobile communication terminal or the change of a common carrier. The SIM card has a processor and a memory chip mounted therein to store information for operation of the mobile communication terminal and includes user information and related information, such as telephone numbers and network numbers.
However, the mobile communication terminal having the smart card does not include a structure for implementing a digital broadcasting CAS, resulting in a need to consider a counterplan.